#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>

using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

const int N = 100005;

int n, m, x, a, b, maxi;
vector <int> arb(N, 0);

void Update(int nod, int st, int dr)
{
    if(st == dr){
        arb[nod] = x;
        return ;
    }

    int m = (st + dr) >> 1;
    if(a <= m) Update(2*nod, st, m);
    else Update(2*nod+1, m+1, dr);

    arb[nod] = max(arb[2*nod], arb[2*nod+1]);
}

void Find(int nod, int st, int dr)
{
    if(a <= st && dr <= b)
    {
        maxi = max(maxi, arb[nod]);
        return;
    }

    int m = (st + dr) >> 1;
    if(a <= m) Find(2*nod, st, m);
    if(m < b) Find(2*nod+1, m+1, dr);
}

int main()
{
    fin>>n>>m;
    for(int i=1; i<=n; i++)
    {
        fin>>x; a = i;
        Update(1, 1, n);
    }

    while(m--)
    {
        bool cod;
        fin>>cod;
        if(!cod){
            fin>>a>>b;
            maxi = -1;
            Find(1, 1, n);
            fout<<maxi<<'\n';
        }
        else{
            fin>>a>>x;
            Update(1, 1, n);
        }
    }


    return 0;
}